ASMPT: Innovative Bonding for Power Electronics

Estimated reading time: 2 minutes

ASMPT presents with its SilverSAM™ SilverSAM machine a highlight for makers of modern power electronics: an innovative and versatile silver sintering machine that meets the great demands on bonding, which is particularly critical in the field of electromobility. SilverSAM sets new standards in interconnect technology for power electronics, particularly in the rapidly growing electric vehicle market.

Heat generation at the joints is unavoidable in power modules. With traditional bonding methods using tin or lead, however, this tends to create problems because the different materials expand at different rates when they get warm. This creates mechanical stresses that soft solder joints are often unable to cope with.

Sintering instead of soldering

One solution to this problem is silver sintering, which uses heat and pressure to solidify the silver-based solder paste far below the metal’s melting point (961°C or 1,762°F). Such a connection is characterized by high electrical and thermal conductivity and remains stable even under strong temperature fluctuations.

ASMPT’s versatile SilverSAM platform sinters silver particles into the previously applied paste with a combination of pressure, temperature, and time in a vacuum or in a nitrogen atmosphere, both of which are oxidation-free and copper-friendly environments. The machine operates with up to three presses with temperatures of up to 300 °C (572 °F) and a pressure of up to 30 mPA.

Versatile and easily scalable platform

The machine has an automatic tool changer and can process many materials, such as DBC (direct bonded copper) and AMB (active metal brazing). The SilverSAM also supports processes using wet and dry pastes as well as die transfer films.

With features like these, the SilverSAM opens the door to a wide range of applications in the volume production of power modules as well as in the assembly of heat sinks. One major area of application is in the rapidly growing market for electric vehicles with its modern DC fast-charging stations.

Complete sintering line from ASMPT

“Our product portfolio covers almost the entire sintering process,” says Dr. Johann Weinhändler, Managing Director of ASMPT AMICRA and in charge of ASMPT Semiconductor Solutions in Europe. “Our versatile DEK Galaxy printer applies the solder paste, our HiPO oven dries it, our POWER VECTOR platform places the components, and our SilverSAM platform does the sintering.” If you employ solutions from technology and market leader ASMPT, you get everything from a single source.”